A

Additional visual function tests 32

color vision 35

contrast sensitivity function 33

glare test 34

good or preferred eye 35 visual field 32

Albinism and aniridia 121 Aphakic child 131

Assessment of needs of visually disabled patient 18

Assistive technologies 74

B

Basic nonoptical devices for low vision patients 157

Bifocals in high additions 46

C

Cardiff acuity cards 134 Cataract 113

Catford drum test 134 Causes of childhood blindness

worldwide 8 Central vision loss 92 Child and toys 166

Classroom modifications 168 Computer based systems 75 Computer education software 76 Contact lenses 71

Corneal damage 117

D

Disability network in India 170 facilities and benefits 171

air travel concessions 171 award of dealership by oil

companies 171 concessions on railways

171 conveyance allowance 171 customs/excise 171 economic assistance by

public sector banks 172

educational allowance 171 income tax concession 171 postage 171

posting 171 Distance acuity 132 Distance vision 25

E

Economic burden due to childhood blindness in

India 9 Electro-optical devices 77 Electrophysiological tests—visual

evoked response 135

F

Functions of a rehabilitation counselor 147

CCTV video magnification systems 148

194 Low Vision Aids

computer usage 148 follow-up care 149 funding issues 148 general eyewear 147

light and glare control 148 optical aids for use at near, distance and

intermediate 148 Patient and family education/

counseling/

psychological, psychiatric consultation 148

mobility and orientation training 148

school education 148

visual field rehabilitation 148 vocational counseling 148

G

Glaucoma 112 Government rehabilitation

services 172 objectives 172

acts in disability 173 national awards 173 Grant-in-aid schemes of the

ministry of social justice and empowerment 173

H

Hand magnifiers 47 Homonymous hemianopia and

optic atrophy 115

I

Image quality with reading spectacles 45

Impairment disability categories 5

Independent living devices 80

Indirect assessment of visual acuity in infants 135

fixation 135

follow movements 135 pupillary reaction 135 reflex responses 135

Instructions to use some nonoptical devices 103

notex 105 reading lamp 103

signature guide 105 slant reading table 103 writing guide 105

L

Lighting and the reading lamp 59 Low vision 1

blindness 3 economic blindness 3 functional vision 3

functional vision impairment 3

legal blindness 4 normal vision 3 partially sighted child 4 travel vision 4

vision impairment 3 vision rehabilitation 4

Low vision aids 4 Low vision or blind 2

Low vision services 152 primary level 152 secondary level services 152 tertiary level services 152

M

Macular degeneration 110 Magnification considerations in

low vision devices 13 relative size 13

relative distance magnification 14

angular magnification 14 electro-optical magnification

14

Magnifiers 46, 98 hand magnifier 98 stand magnifier 98

Magnifying reading glasses 97 Magnifying spectacles 41 Magnitude of low vision 6 Making text legible for visually

impaired 168 contrast and type color 168 font selections 169

paper finish and distinct covers 169

point size 169 spacing 169

Mobility assisting devices 72 More than 6 years 138

Snellen’s charts 138 Myopic degeneration 124

N

National association for the blind 174

National institute for the visually handicapped 173

Near vision recording 28 Near vision requirements 19

reading disability 20 writing disability 21

Nonoptical devices 58

Number of blind person years 8

O

Occlusion test 135 Ophthalmoscopic examination

135 Optical design of the magnifiers

50

Optical devices 42

Index 195

Optical quality of the type of lens to be used 44

Optics 54 galilean 54 keplerian 54

Optics of low vision devices 12 Overall blurred vision 90

P

Peripheral vision loss 93 Prediction of ADD 15

reciprocal of Snellen’s visual acuity 15

reciprocal of the distance 15

R

Refraction 30

Refractive errors and low vision 10

Rehabilitating the child with low vision devices 149

Relative size devices 65 absorptive lenses 66 color and contrast

enhancement 70 contrast enhancing lenses/

filters 68

field expanding devices 70 glare 66

glare control devices and filters 68

glare reduction lenses/filters 67

large print materials 65 students and the font size 66

Retinal pathologies 119 Retinitis pigmentosa 108

S

Selecting the devices for partiallysighted 85

196 Low Vision Aids

age of onset of the disease 85 cost of the device 89 educational and occupational

demands 89 eye pathology 85

motivation and psychological factors 89

optical considerations of selecting the device 89

type of field defect 85 Some of the low vision devices

suppliers around the world 187

Some organizations and their websites around the world 189

Some rehabilitation centers in India 177

Standard list for low vision services: vision 2020 155

Suppliers, manufacturers in low vision care 185

T

Telescopes 52

Teller’s acuity cards 133

V

Vision 2020: the right to sight in India 10

Vision evaluation in infants and children 132

Vision impairment and abnormal development 127

Vision recording 26 Vision rehabilitation 145

objective 145

Vision tests in 3 to 6 years 135 Landolts C 135

Lea symbols charts 136 Lippman’s Hotv test 136 tumbling E 135

Vision therapy 161

Vision therapy with computers 164

Visual acuity 25

Visual acuity assessment 39 Visual acuity scales—their

comparative values 17